Piano action



Sap}; 1929. H. B. TODD 1,729,523

PIANO ACTION Filed July 12, 1928 2 sheets-sheen 1 z .I 16 i if v M J4 M 40 15 a Sept. 24, 1929. I H. B. TODD 1,729,528

' PIANO ACTION Filed July 12, 1928 W 2 Sheets-Sheet 2 Patented Sept. 24, 1929 PATENT OFFlCE HAROLD B. TODD, F PHILADELPHIA, FENNSYLVANIA PIANO ACTION Application filed July 12, 1928. Serial No. 282,277.

My invention relates to pianos, pianettes or any stringed instruments adapted to be played by means of keys that operate hammers striking the strings, and has more particular reference to the operating mechanism between the keys and the striking hammers.

A purpose of my invention is to simplify the hammer operating mechanism of a stringed instrument in its adaptation to prevent the hammer from striking its string more than once when the key operating the hammer is struck.

A further purpose is to provide a form of hammer movement well adapted to operation with what might be called pianettes or zitherpianos in which the strings are placed below the keyboard, and also well adapted to use upon other types of pianos, whether upright, square or grand.

A further purpose is to pivot the butt of a piano hammer upon the pivotally mounted butt of a stop member, using the stop member to operate the hammer and to stop its rebound after it has struck its string.

A further purpose is to optionally mount a string damper upon a hammer member so as to engage the string when the key retracts but to be held out of engagement from the string as long as the key operating the hammer is depressed.

Further purposes will appear in the specifications and in the claims.

I have elected to show one main form only of my invention, showing this form however,

applied to different types of stringed instruments, and selecting a form that is practical and efficient in operation and which well illustrates the principles involved.

Figure 1 is a fragmentary vertical elevation showing'my hammer movement applied to a stringed instrument, such as a zitherpiano or pianette, in which the strings are vertically below and approximately parallel to the operating keys of the instrument.

Figure 2 is a corresponding View showing structure embodying my invention applied to an upright piano.

Figure 3 is a detail right end elevation of a portion of Figure 2. Figure 4 is a fragmentary vertical elevation showing structure embodying my invention applied to a grand piano.

Like numerals refer to like parts in all figures.

Describing in illustration and not in limitation and referring to the drawings Structure embodying my invention is ad vantageously used with any of the usual types of piano or other stringed instruments that are operated by striking keys that in turn operate hammers to strike the strings, but I regard it as being particularly desirable for use with stringed instruments, such as zither pianos or pianettes, that have the strings located under the keyboard, and for this reason have in Figure 1 illustrated the invention applied to this type of instrument.

In Figure 1 the reed organ key 10 is piv otally supported 11 and is loosely guided at 12 from suitable rails 13 and 14, respectively.

As soon as the players finger leaves the key the latter retracts under the upward pressure of a sticker member 15 transmitted through the head of a capstan screw 16 that extends downwardly from the bottom of the key.

The sticker is pivotally connected at 17 to a butt member 18 operating the hammer and is laterally guided by a link 19 so as to present its upper end continuously against the downwardly presented head of the capstan 1 .L

The link 19 has pivotal connection at one end to the sticker and at the other end to a stationary bracket 20 from a rail 21.

The operating butt member 18 is pivoted at 22 to a stationary bracket 23 and gives pivotal support at 24 to a second butt member 25 that carries the hammer 26 at the outer end of the hammer shank 27.

The butt member 18 carries an operating stick 28 in the plane of movement of the hammer, the forward side of the stick normally engaging deadening felt 29 on the back of the hammer.

A spring 30 is fastened at one end to the lower side of a rail 31 and presents its free end at 32 against the hammer butt 25 thereby pressing the hammer upwardly into engagement with the stick at 29. It also pushes the stick upwardly into engagement with a felt stop 33 on the lower side of the rail 1%, and resiliently supports the sticker in its position for holding the key up.

hen the key is depressed the sticker moves down and throws the operating stick from its retracted position in which it is pressing against the felt 29 to the position shown in dot-and-dash in which the stick has been brought to rest by a deadening stop 34 upon the rail 35.

The operating stick throughout its down ward throw pushes the hammer ahead of it so that when the stick comes to rest against the stop 3% the hammer is moving at relatively high velocity and flies on beyond the stick to strike the string 36 and rebounding from the string comes to rest against the operating stick, the deadening engagement at 29 pre venting a return rebound against the string.

In the form of instrument shown in Figure 1, I may desirably mount a damper member 37 upon a suitable rearward extension 38 from the hammer member.

The position of the damper is such that it is maintained out of engagement with the string of the piano during full deflection oi the key and effects the damping engagement with the string as soon as the key retracts upwardly.

In operation finger depression of the key pushes down the sticker which throws the operating butt member and stick and hammer down toward the string and the damper away from the string. The operating member ceases its downward movement when it engages the stop 3%, the hammer moving onward, striking the string and then retracting against the stop member.

The damper 37 is raised from the string by the turning movement of the butt of the hammer before the hammer engages the string and is out of engagement with the string as long as the stick is in its low position, corresponding to key depression.

As soon as a player releases the key, the key rises under the action of the spring and the intermediate connections, the hammer and operating members moving upwardly about the pivot 22 causing the sticker to rise which pushes up the key at the capstan 16.

This movement is particularly convenient for use with pianettes or zither-pianos in which the relatively short strings are placed under the keyboard and the tightening screws 39 are ranged for easy access below and in front of the keys.

In Figure 2, substantially the same double butt mechanism is applied to operate the hammer mechanism of an upright piano.

The key 40 is pivoted upon usual balance key pins 421. Front key pins 412 guide the key so as to maintain it in the same vertical plane. The capstan screw l3 iresents its head under the lower end of the sticker 44, the weight of the sticker member and of its guiding link and of the damper wippen 46 serving to retract the key.

The upper end of the sticker has pivotal connection at 17 to the operating butt member 18, which has a pivotal support at 22 upon a stationary bracket 23 and at 2st gives pivotal support to the butt 25 of the hammer 26.

The stick 28 and hammer are normally damped by a deadening felt contact at 29' and move in the same vertical plane, the stick norr ally resting against the deadening stop 35 from which position it is thrown forward when the key is depressed until it comes against the deadening stop 3 1, the hammer pushed along ahead of the stick, flying onward when the stick comes to rest and striking the key.

In the form shown in Figure 1, I mount the damper mechanism upon the same member that carries the hammer, but as illustrated in Figure 2, I prefer, with uprightpianos, to mount this mechanism in any usual or suitable way, as upon a rocker member 47.

The rocker 17 is pivotally supported at- 48 on a stationary bracket l9 and extends upwardly to present a damper 50 against the string when the key is in raised position, and away from the string when the key is depressed.

The rocker 47 is spring-pressed at 51 toward its damping position and its lower end presents a felt 52 to the operating toe 53 of the damper wippen 46.

The damper wippen is pivotally supported near one end at El upon a suitable stationary bracket 55, its other end being supported by the bottom of a slot 56 through the sticker. he wippen is rocked about its pivot, to 0perate the damper, by the vertical movement of the sticker il 1t. Upward movement of the sticker moves the damper wippen upwardly and its operating toe 53 outwardly to swing the damper away from the string 36. The damper moves back against the string under the action of the spring 51.

It will be seen that the operation except with respect to the dampin is essentially the same as already described l or Figure 1.

Figure 4 shows the movement applied to operate the hammer of a grand piano.

The operating butt and stick member is here pivoted at 22 upon a stationary bracket 23 from a rail 57 and is operated by a sticker 15 which is pivotally connected at 1'4" to the stick member and is guided by the link 19 so as to present its lower end against the head of a capstan 16 that is carried upon the key 10 The key pivots upon the usual balance key pins 57, is vertically guided by the key pins Eji 58 and is rearwardly extended beyond the capstan to operate damper mechanism.

A damper 37 is carried upon the upper end of a rod 58 vertically guided at 59 and pivotally supported at 60 upon the outer end of a link 61 that is in turn supported and raised and lowered by a felt 62 on the rearward end of the key lever.

When the key is depressed the damper lifts from the string 36 returning. to position against the string when the key retracts to its normal position.

The hammer butt 25 is pivoted. as in the other forms at 24 upon the operating butt member 18 the hammer presenting a deadening felt 29 against the stick member 28 The hammer and stick members are shown spring pressed together at 68; optionally, this spring may be dispensed with and the weight of the hammer retracting the hammer against the stick.

The stick has a range of movement be tween the deadening stop members 83 and 3 1 that are essentially the same as the corresponding stop members in the other forms.

N hen the forward end of the rey is depressed, the capstan rises and lifts the sticker to throw the stick and operating butt member upwardly away from the stop 33 and into the stop 84 During this movement, the stick carries the hammer ahead of it and when the stick comes to rest against the stop 33 the hammer fiies on upward into the string and re bounding strikes the stick at the deadening felt 29 It will be obvious that the movement shown in all forms is the same in so far that each presents what might be called a double butt mounting for the hammer, the hammer being pivotally mounted upon an operating butt and stick member that has stationary pivotal pport and that has range of movement between fixed stops during which it is adapted to move as a unit with the hammer structure, the hammer flying forward as the operating butt comes to rest to strike the string and rebounding into engagement with the operating stick.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such in so far they fall. within the reasonable spirit and scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Pa'tent lo 1. In a piano action, a fixed bracket, a butt member pivoted thereon, a key-operated sticker engaging the butt member to move it about the pivot, a hammer shank pivotally attachcd to the butt member, a hammer carried by the shank, an operating stick carried by the butt member and normally engaged by the hammer, and a spring normally pressing the hammer toward the operating stick.

2. In a piano action, a fixed bracket, a butt member pivoted thereon, a key-operated sticker engaging the butt member to move it about the pivot, a hammer shank pivotally attached to the butt member, a hammer carried by the shank, an operating stick carried by the butt member and normally engaged by the ammer, and a spring normally pressing the hammer toward the operating stick and the operating stick in a direction to lift the key.

3. in a piano action, a fixed supporting bracket, a butt member pivotally connected therewith, a key-operated sticker adapted to move the butt member about its pivot toward striking pisition and normally in keyraising position, an operating stick carried by the butt member, a hammer shank pivotally carried by the butt member, a hammer on the shank, a spring pressing the hammer shank toward the operating stick, cushion stops for the operating stick and between the hammer and stick, and a second stop for the operating stick controlling its movement with the hammer and beyond the position of which the hammer moves free from the stick to strike its blow.

4. In a piano action, a fixed support, a butt member pivoted to the support and normally in retracted position, a key-operated sticker adapted to throw the butt member from retracted position, an operating stick movable with the butt member, a hammer shank and hammer pivotally movable with respect to the operating stick, cushion stops for the retracted position of the operating stick and between the operating stick and the hammer, a damper movable with the butt member to apply the dan'iper in retracted position of the butt member and to release it with operating movement of the operating stick and spring means for pressing the hammer shank and hammer toward the operating stick.

5. In a piano action, a fixed bracket, a butt member pivotally supported thereon, operatmeans for throwing the butt member, a hammer shank, a hammer pivotally supported with respect to the butt member, an operating stick carried by the buttmember and normally engaged by the hammer, a spring means for pressing the hammer shank toward. the operating stick, a piano string adapted to be engaged by the hammer, a stop for the operating stick stopping it short of the point at which the hammer would strike the piano string, and cushion stops on opposite sides of the operating stick to stop it in retracted position and to stop movement of the hammer toward the stick.

HAROLD B. TODD. 

